The news comes on the heels of DoubleClick unveiling a multi-pronged privacy initiative aimed at deflecting the complaints lodged against it by privacy advocates. The effort involves a banner ad campaign, a new Web site, and the creation of a board of privacy experts to advise DoubleClick.

In the documents filed by DoubleClick regarding its proposed new offering of stock, the company said it received a letter from the FTC on February 8 informing the company that it was the subject of an inquiry.

The Electronic Privacy Information Center, an advocacy group, filed a complaint with the FTC last week, alleging that DoubleClick engaged in unfair and deceptive trade practices relating to its compilation of data about Internet users.

The documents also show that DoubleClick faces six privacy-related lawsuits filed over the past few weeks. Although four of these suits had previously been made public, two that were filed on January 28 were not revealed until now.

Although DoubleClick admits that these lawsuits were only recently filed, it said, “we believe these lawsuits are without merit and we intend to vigorously defend ourselves against them.”

Decorse v. Doubleclick was filed in the Superior Court of the State of California, Marin County, and alleges that the ad company engaged in unlawful business practices by collecting and using information about Internet users. The complaint seeks damages and injunctive relief.

The second newly-revealed suit, Steinbeck v. Doubleclick, alleges similar violations, but it was filed in U.S. District Court in California and cites federal law.

DoubleClick has been under increased fire from privacy advocates since its acquisition of Abacus Direct, which has databases of consumers’ offline purchasing behavior. The company wants to put together that offline data with the information it’s gathering online, so it can better target the ads it serves.

Privacy advocates contend that DoubleClick isn’t doing a good enough job of informing people that data about them is being collected. They also think DoubleClick should allow consumers to opt-in to the data collection system, rather than being forced to opt-out.

Emotion can be very powerful when trying to reach an audience, and it can be boosted by linking it with the way memory affects human behaviour. How can all of this apply to the demanding mobile audience?